• Title/Summary/Keyword: key technology

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Enhanced drought and salinity tolerance in transgenic potato plants with a BADH gene from spinach

  • Zhang, Ning;Si, Huai-Jun;Wen, Gang;Du, Hong-Hui;Liu, Bai-Lin;Wang, Di
    • Plant Biotechnology Reports
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    • v.5 no.1
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    • pp.71-77
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    • 2011
  • Drought and salinity are the most important abiotic stresses that affect the normal growth and development of plants. Glycine betaine is one of the most important osmolytes present in higher plants that enable them to cope with environmental stresses through osmotic adjustment. In this study, a betaine aldehyde dehydrogenase (BADH) gene from spinach under the control of the stress-induced promoter rd29A from Arabidopsis thaliana was introduced into potato cultivar Gannongshu 2 by the Agrobacterium tumefaciens system. Putative transgenic plants were confirmed by Southern blot analysis. Northern hybridization analysis demonstrated that expression of BADH gene was induced by drought and NaCl stress in the transgenic potato plants. The BADH activity in the transgenic potato plants was between 10.8 and 11.7 U. There was a negative relationship (y = -2.2083x + 43.329, r = 0.9495) between BADH activity and the relative electrical conductivity of the transgenic potato plant leaves. Plant height increased by 0.4-0.9 cm and fresh weight per plant increased by 17-29% for the transgenic potato plants under NaCl and polyethylene glycol stresses compared with the control potato plants. These results indicated that the ability of transgenic plants to tolerate drought and salt was increased when their BADH activity was increased.

Preparation and Characterization of Core/Shell-type Ag/Chitosan Nanoparticles with Antibacterial Activity

  • Lin, Yue;Jing, Wang;Kang, Pan;Xiaoming, Zhang;Zhouping, Wang;Wenshui, Xia
    • Bulletin of the Korean Chemical Society
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    • v.32 no.4
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    • pp.1277-1281
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    • 2011
  • Making use of chitosan (CS) and ethylenediaminetetraacetic acid (EDTA) as a reaction system, CS-EDTA nanoparticles were synthesized through a facile counterion complex coacervation method. $Ag^+$ could enter porous CS nanoparticles synthesized with this method, allowing Ag nanoparticles within chitosan nanoparticles were synthesized by reducing silver nitrate with chitosan. Because of the noncovalent interaction between CS and EDTA, the EDTA could be easily removed via dialysis against water, and pure core/shell-type Ag/CS nanoparticles could be obtained. The nanoparticles showed higher antibacterial activity toward E. coli than the active precursor Ag nanoparticles and CS.

Improved performance of polyamide nanofiltration membranes by incorporating reduced glutathione during interfacial polymerization

  • Jiao, Zhiwei;Zhou, Linjie;Wu, Mengyuan;Gao, Kang;Su, Yanlei;Jiang, Zhongyi
    • Korean Journal of Chemical Engineering
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    • v.35 no.12
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    • pp.2487-2495
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    • 2018
  • Inspired by the specific amino acid sequence Asn-Pro-Ala (NPA) of water channel aquaporins (AQPs), we fabricated polyamide (PA) nanofiltration (NF) membranes by introducing reduced glutathione (GSH) in interfacial polymerization (IP) method. Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectrometry (XPS), scanning electron microscope (SEM), atomic force microscopy (AFM), zeta potential and static water contact angle measurement were employed to characterize the chemical composition, morphology, electronegativity and hydrophilicity of the NF membranes. The water flux of GSH/PIP-TMC NF membrane reached $32.00L\;m^{-2}h^{-1}$ at 0.2 MPa, which was approximately twice than that of pristine PIP-TMC NF membrane when the ratio of GHS to piperazidine (PIP) was 40% during IP process. More water channels were built as GSH was embedded into PA layer. The fabricated NF membranes also took on potent rejection for dyes and $Na_2SO_4$. This study presents a simple and facile method to simulate water channels-based biological materials which may find potential application in water treatment.

High Repetition Wavelength-locked 878.6 nm LD Dual-end-pumped Nd:YVO4 1064 nm Laser

  • Li, Yue;Yu, Yong-Ji;Wang, Yu-Heng;Liu, Hang;Liu, He-Yan;Jin, Guang-Yong
    • Current Optics and Photonics
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    • v.2 no.6
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    • pp.582-588
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    • 2018
  • A $Nd:YVO_4$ laser dual-end-pumped by a wavelength-locked 878.6 nm laser diode is presented. At the repetition rate of 500 KHz, the absorbed pump power of 58 W, an output power of 26.1 W at 1064 nm is obtained, corresponding to an optical-optical efficiency of 45%. The pulse width is 44.2 ns. Meanwhile, the effects of traditional 808 nm pumping and 878.6 nm dual-end-pumping on the output laser beam quality and pulse width are compared and analyzed in an experiment.

Wide-Tunable Mid Infrared Intra-cavity Optical Parametric Oscillator Based on Multi-period MgO:PPLN

  • Wang, Xiao-Chan;Wang, Yu-Heng;Zheng, Hao;Liu, Hong-Zhi;Yu, Yong-Ji;Wang, Zi-Jian
    • Current Optics and Photonics
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    • v.5 no.1
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    • pp.59-65
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    • 2021
  • This paper reports a tunable diode-pumped folded intracavity Q-switched singly resonant optical parametric oscillator based on multi-period MgO:PPLN. A wide tuning mid-infrared parametric light from 2.78 ㎛ to 4.17 ㎛ was obtained in real time by changing the poled periods and temperatures. The maximum output power of 1.89 W at 3.2 ㎛, 1.53 W at 3.5 ㎛, 0.87 W at 3.8 ㎛ and 0.486 W at 4.1 ㎛ were achieved. The highest optical-optical conversion efficiency was 7.89%. During experiments, a range tunable output of 2.78-4.17 ㎛ in the mid-infrared range was achieved.

Physical, Chemical Properties and Structural Changes of Zaodan Pickled by Vacuum Decompression Technology

  • Sun, Naxin;Liu, Huiping;Zhang, Xiaowei;Wang, Hongni;Liu, Shaojuan;Chen, Pei;Yu, Weijie;Liu, Kai
    • Food Science of Animal Resources
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    • v.38 no.2
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    • pp.291-301
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    • 2018
  • To shorten the production cycle of Zaodan, this study first pickled Zaodan by a novel technology - vacuum decompression technology. Vacuum decompression technology could reduce the pickling time of Zaodan from 20 wk to about 9 wk. The protein content, moisture and pH of the Zaodan egg white gradually decreased with a concomitant increase in salt during the pickling process. The total sulfhydryl group (SH) group content of the egg white proteins was increased to $2.43{\times}10^{-3}mol/L$ after being pickled for 30 d, whereas the content of disulphide bonds (SS) was reduced to $23.35{\times}10^{-3}mol/L$. The surface hydrophobicity was lowest after pickling for 30 d. In addition, great changes occurred in the secondary structure of the egg white proteins after pickling for 20 d. The disappearance of ovomucin was noticeable based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis.

HRKT: A Hierarchical Route Key Tree based Group Key Management for Wireless Sensor Networks

  • Jiang, Rong;Luo, Jun;Wang, Xiaoping
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.8
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    • pp.2042-2060
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    • 2013
  • In wireless sensor networks (WSNs), energy efficiency is one of the most essential design considerations, since sensor nodes are resource constrained. Group communication can reduce WSNs communication overhead by sending a message to multiple nodes in one packet. In this paper, in order to simultaneously resolve the transmission security and scalability in WSNs group communications, we propose a hierarchical cluster-based secure and scalable group key management scheme, called HRKT, based on logic key tree and route key tree structure. The HRKT scheme divides the group key into cluster head key and cluster key. The cluster head generates a route key tree according to the route topology of the cluster. This hierarchical key structure facilitates local secure communications taking advantage of the fact that the nodes at a contiguous place usually communicate with each other more frequently. In HRKT scheme, the key updates are confined in a cluster, so the cost of the key updates is reduced efficiently, especially in the case of massive membership changes. The security analysis shows that the HRKT scheme meets the requirements of group communication. In addition, performance simulation results also demonstrate its efficiency in terms of low storage and flexibility when membership changes massively.

Identification and functional prediction of long non-coding RNAs related to oxidative stress in the jejunum of piglets

  • Jinbao Li;Jianmin Zhang;Xinlin Jin;Shiyin Li;Yingbin Du;Yongqing Zeng;Jin Wang;Wei Chen
    • Animal Bioscience
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    • v.37 no.2
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    • pp.193-202
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    • 2024
  • Objective: Oxidative stress (OS) is a pathological process arising from the excessive production of free radicals in the body. It has the potential to alter animal gene expression and cause damage to the jejunum. However, there have been few reports of changes in the expression of long noncoding RNAs (lncRNAs) in the jejunum in piglets under OS. The purpose of this research was to examine how lncRNAs in piglet jejunum change under OS. Methods: The abdominal cavities of piglets were injected with diquat (DQ) to produce OS. Raw reads were downloaded from the SRA database. RNA-seq was utilized to study the expression of lncRNAs in piglets under OS. Additionally, six randomly selected lncRNAs were verified using quantitative real-time polymerase chain reaction (qRT-PCR) to examine the mechanism of oxidative damage. Results: A total of 79 lncRNAs were differentially expressed (DE) in the treatment group compared to the negative control group. The target genes of DE lncRNAs were enriched in gene ontology (GO) terms and Kyoto encyclopedia of genes and genomes (KEGG) signaling pathways. Chemical carcinogenesis-reactive oxygen species, the Foxo signaling pathway, colorectal cancer, and the AMPK signaling pathway were all linked to OS. Conclusion: Our results demonstrated that DQ-induced OS causes differential expression of lncRNAs, laying the groundwork for future research into the processes involved in the jejunum's response to OS.

Prediction of dryout-type CHF for rod bundle in natural circulation loop under motion condition

  • Huang, Siyang;Tian, Wenxi;Wang, Xiaoyang;Chen, Ronghua;Yue, Nina;Xi, Mengmeng;Su, G.H.;Qiu, Suizheng
    • Nuclear Engineering and Technology
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    • v.52 no.4
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    • pp.721-733
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    • 2020
  • In nuclear engineering, the occurrence of critical heat flux (CHF) is complicated for rod bundle, and it is much more difficult to predict the CHF when it is in natural circulation under motion condition. In this paper, the dryout-type CHF is investigated for the rod bundle in a natural circulation loop under rolling motion condition based on the coupled analysis of subchannel method, a one-dimensional system analysis method and a CHF mechanism model, namely the three-fluid model for annular flow. In order to consider the rolling effect of the natural circulation loop, the subchannel model is connected to the one-dimensional system code at the inlet and outlet of the rod bundle. The subchannel analysis provides the local thermal hydraulic parameters as input for the CHF mechanism model to calculate the occurrence of CHF. The rolling motion is modeled by additional motion forces in the momentum equation. First, the calculation methods of the natural circulation and CHF are validated by a published natural circulation experiment data and a CHF empirical correlation, respectively. Then, the CHF of the rod bundle in a natural circulation loop under both the stationary and rolling motion condition is predicted and analyzed. According to the calculation results, CHF under stationary condition is smaller than that under rolling motion condition. Besides, the CHF decreases with the increase of the rolling period and angular acceleration amplitude within the range of inlet subcooling and mass flux adopted in the current research. This paper can provide useful information for the prediction of CHF in natural circulation under motion condition, which is important for the nuclear reactor design improvement and safety analysis.

Lipid accumulation mediated by adiponectin in C2C12 myogenesis

  • Yin, Changjun;Long, Qinqiang;Lei, Ting;Chen, Xiaodong;Long, Huan;Feng, Bin;Peng, Yin;Wu, Yanling;Yang, Zaiqing
    • BMB Reports
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    • v.42 no.10
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    • pp.667-672
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    • 2009
  • Plasma concentrations of adiponectin have been shown to be decreased in patients with obesity, cardiovascular diseases, hypertension and metabolic syndrome. Recent studies have found that adiponectin reduces lipid accumulation in macrophage foam cells which may impact the development of atherosclerosis. However, it remains unclear whether adiponectin is involved in the process of lipid accumulation during myogenesis. Using C2C12 myoblasts, we investigated the effect of adiponectin on intramyocellular lipid accumulation during myogenesis. The results showed that intracellular lipid accumulation is significantly decreased during C2C12 differentiation, apparently due to increased fatty acid oxidation and decreased fatty acid synthesis during this process. C2C12 cells transiently transfected with adiponectin gene showed reduced lipid accumulation as compared to controls. Further experiments demonstrated that adiponectin can suppress lipid accumulation by increasing fatty acid oxidation during C2C12 myogenesis.